RIO DE JANEIRO, Brazil — President Luiz Inacio Lula da Silva called in the Brazilian air force Friday to help transport airline passengers on an emergency basis as long delays and overcrowded planes snarled commercial flights over the busy holiday weekend.

The Air Force Command said it was fulfilling a request by Silva to “relieve the difficulties currently faced by users of commercial civil aviation.” All expenses will be “fully repaid by the airlines.”

The air force was making eight jets — two Boeing 707s, two Boeing 737s and four Embraer EMB-145s — available for flights between Brasilia, Sao Paulo and Rio de Janeiro.

Bad weather and mechanical problems with six Tam airplanes exacerbated flight delays at Brazilian airports Thursday, causing delays of up to 12 hours.

The National Agency of Civil Aviation said it halted Tam ticket sales Friday because “predicted improvements in the treatment of passengers did not occur, with the persistence of delays.”

TAM officials could not be reached for comment.

More than 1,000 stranded travelers were waiting for delayed flights Friday in Brasilia, including some 600 Tam passengers, Infraero said in a statement. Some 30 passengers invaded the tarmac, chanting “we want a plane,” but were peacefully removed by police.